.ChildPage {
    position: fixed;
    top: 0;
    left: 100%;
    width: 100%;
    height: 100%;
    z-index: 999;
    background: #f0f0f0;
    transition: left .35s;  
}

.ChildPage.active {
    left: 0;
}

.ChildPage-title {
    background: rgb(224, 86, 86);
    padding: 10px;
    color: #f0f0f0;
    font-size: 16px;
    text-align: left;
}